Rotary engines



Jan. 27, 1959 Y. G. BREELLE ROTARY ENGINES 4 Sheets-Sheet 1 Filed Nov.14, 1957 INVENTOR .ATTORNEYS n- 27, 1 I I Y. L. G. BREELLE 2,870,752

ROTARY ENGINES Filed Nov. 14, 1957 4 Sheets-Sheet 2 Fig. 3

LA\ Pg Fi 5b Pl-P5 PZP' INVENTOR W; S 5 & BRccuc JZ L. .31L BY WATTORNEYS 4 Sheets-g 3 INVENTOR 31 Brice w 4 /M ATTORNEYS Jan. 27, 1959Y. L. G. BREELLE I ROTARY ENGINES Filed Nov. 14, 1957 Yves L. G.Breelle, Rueil-Malmaison, France, assignor to Institut Francais duPetrole, des Carburants et Lubrifiants, Paris, France I v ApplicationNovember 14, 1957, Serial No. 696,538- Claims priority, applicationFrance November 14, 1956 16 Claims. Cl. 123-43 This invention relates toimprovements inrotary enatent O gines, and more particularly in suchengines comprising I internal combustion rotors.

It is an object of my invention to provide improve,

ments in rotary engines having rotary internal combustion, means,whereby the cooling and scavenging of the engine I gines comprisinginternal combustion rotors, which en-..

ice

2 are disposed symmetrically to the central axis of the combustionrotor.

As a further; important feature of the invention, the Wells in thecombustion rotor being interconnected with each other by the aforesaidconduit. means are so coordinated in their function with the remainingrotary elements of the rotary engine, that after each combustion andpower stroke or period, the end of the compression period involving thecharge of the Wells with a new fuel mixture prior to combustioncoincides with a scavenging of the entire co-mbustionspace from whichresidual gases are expelled by the newly introduced gases. At the sametime, losses due to fresh gases escaping directly through the exhaustmeans of the engine are maintained at a minimum. One or several pairs ofwells may be provided in the combustion rotor, the two wells of eachpair being disposed preferably diametrically relativeto each other andconnected by a channel extending substantially transversely to the rotoraxis. The wellsof each pair may also be disposed adjacent each other andconnected by a channel through the interior of the rotor.

- Thecombination of the aforesaid features of the invention in theinternal'combustion rotor contributes to a most effective cooling of thelatter in a uniform manner, due firstly to (a) the limitation of thecombustionspace a to wells and interconnecting conduits, (b) thegeometrigines are described in my patent application Serial Number574,833, filed on March .29, 1956, and the continuation-in-partapplication thereof, filed on October 8, 1957,

under Serial Number 688,908.

In all those rotary engines having rotary internal combustion means,which are at present known in the art,

a main problem that has to be solved is that of non-' uniform thermalexpansion and contraction of the rotary elements in the casing. Theserotary elements normally comprise considerable compact. metallic masses,and it deformations of the rotor bodies and correspondingly to eitherbinding effects or deterioration of the bearing and sealing means of therotary elements, and consequently shorten the life time of theseengines.

While the choice of expensive alloy materials having small thermalexpansion coefficients may offer at least a partial solution to thatproblem, I have invented improvements in the structure, in particular ofthe rotary elements of rotary internal combustion engines, which largelyeliminate the above described drawbacks and permit to attain the objectsstated hereinbefore.

The improved rotary engine with rotary internal combustion means,according to my invention, comprises, as a main feature, at least oneinternal combustion rotor provided with recesses or wells for thepassage therethrough of the rotary pistons of the central rotorcharacteristic of rotary engines, which wellsserve at the same time asthe combustion chambers proper of the internal combustion rotor. v I

As a further important feature, these several chambers, hereinafterreferred to for the sake of brevity as wells, are interconnected byinternal channel or conduit means provided in the combustion rotor'so asto constitute a important uniformity of thermal dimensional changes ofthe combustion rotor, these channel or conduit means pally: symmetricalarrangement of the combustion space in the rotor body, (0) sufficientspace left in the rotor body for large cooling cavities and/or conduits,and (d) contribution of the scavenging step in the rotor to a uniformcooling 'of the latter by the fresh combustion gases.

In a preferred embodiment of the invention, the im proved rotary engineaccording to my invention comprises a combustion rotor having the, abovedefined characteristics, and a central rotor bearing a determined numbern of pistons? or large protrusions in the cylindrical wall of. therotor, which are distributed about the shaft ofthe central rotor spacedfrom each other under' an angle of and at least one sealing rotor in anengine block of easing provided with the necessary means forsynchronising the movement of the various rotors, intake and exhaustmeans associated with, and conduits provided in the casing.

This type of engine is described in detail in my patent application andcontinuation-in-part appl'iaction supra.

In the same'manner, my improved rotary engine may comprise two or moreinternal combustion rotors embodying the above described characteristicfeatures.

Each of the combustion rotors may be provided with a number of 22combustion wells distributed about the relative to each other.

And each gate rotor may be provided with a number of p gate or valvewells distributed about the central axis of the gate rotor under anangle of p relative to each other.

Furthermore, the improved rotary engine according to my invention maycomprise a central rotor bearing a plurality of pistons distributedirregularly about the periphery of the central rotor, while the wells inthe peripheraLJotors, i. e. the internal combustion rotor of PatentedJarnZY, th h 3 rotors and the gate rotor or rotors, are correspondinglydisposed irregularly about'the peripheries of their respectwo rotors soas to permit passage of the pistons therethrough during the rotationo'fthe central rotor.

However, the ab'ove rrientioned'regular disfribution of pistons aboutthe periphery of the central rotorjisjp re ferred since it permitsa'better balancing-of the iner,1and consequently also oftheiperipheralrofofs. M

Thus, thelce'ntral rot'onandthe peripheral'rotors, preferably of thetypes described inmy patent; appl 1 tion and continuation-impartapplication supra.

The invention will be better understoodfl frorn the, subsequent detaileddescription thereof in corinection lv vifh, the accompanying drawings'in which: I v

Figure 1 is;a=vertical tiransvers sf ctional View through a rotaryengine constructedin accordance with the invention, th'e'sec'tionlbe'ingtaken along line IjI in Figurez; 7,, 4

Figure lzz -shows a partial sectional view of the exhaust region shownin Figure ljl having ansomewhat different structure; I I

Figure 2 is a vertical longitudinal ,sectional' view of. the: rotaryengine shownin Figure 1' along line IIY II. there? my p I V Figure-3 isa perspective, partially sectionalview of one embodiment of'a combustionT FQL according. toithe invention; i V V v Figure 4 illustrates inperspective and partiallyinseo. tion' another embodiment of'aemusnqamter and. a. corresponding central rotor in accordanc'e withjthe'invenw l: fiongi, a

Figures 5a and 5b show contour lines in, different I transverseplanesfof a'Welhofithekorhbhstiof rotor,v and V of a pistonofthecent'ral rotorprespectiyely, whicli lare l both illustrated inFigure Figure 6 illustrates yet anotherembodiment .ofa corn,- bustion''r'otor "according to the; inv'en irficrossgs g, .5, v v ..1

Figure 7'-isa vertical transverse sectional viewtofiann otherembodimentfof a rotary'enginefcon'structedfi accordance with theinvention, whi c h enginejcornprises.

two combustion rotors ajnd a'centraljrotor,bearingfive I pistons; iFigures 8a and 8e illustrate schematically five different positions ofthe combustionr'otor, the central rotor and the gate rotor of the rotaryengine illustrated in Figures 1 and 2. t v

na cw o e raw n ,more in l ai ndi Particular dl s resl' hi r pre nt asimple... embodiment o the proved rota y;en n ,a cordi gs o.7 theinvention,'the engine block or'casing 1 is provided with an externalwall 2 and internal wall, land-a plurality of cooling spaces dinte thesewallg '4 I Q Q LB ell, nt al,substantiallyicy u: drical space: definedby the aternal cylinder, surface 5', and l peripherally disposed i elativei the afore aid-cylinder.

V I T U d fia dbrin ternal surface. portions; 51am 7 .-of-th e nnenyvallZi -The I central axes. of the mus we cylindrical-,space s t-extendparallel to the central axis of theaforesaid cylinder space.

In the central axis of the latter space, there extends a main engineshaft 10 on whichthere is mounted a central rotor 11. This central rotor11 bears along-,its-mxternal nd ca u aae t o r b-shared pis ns fi ead 14i pose Q PP9-5i L of he ce tralrdto -1Land extending parallel to the cetral axi ;ot:thes1a ter;.;,

The pistons 13 and 14 are preferably of a cross-section similar to thatof the teeth..o':'a gear and their exact contours are determined asdescribed in my copending patent application Serial No, 688,908 supra'fDue 7 the rotation of 'thecentra l frotor 11' wliich shall-hopssumed to'be always in'clockwisedirection; leading slopes; 13a, 14a, and trailingslopes 13b, '14b ofpistons 13 and 4 14 can be' distinguishe'dt"The"end'surfaces' lfa' and 16 Y of these pistons are" preferablyprovided-with longitudii nally extending grooves and ribs 17. Similarlongitudinalribs and-grooves 17" are also providedaboutthe" cylindricalsurface 12 of central rotor 11. The end faces 18 and 19 of the central"rotor 11 may be provided with annular protrusions 20 and grooves 20a,while they portions 9 of the internal tsurfa'cezof inner wall 3 facingthese rotor end faces 1,8 an.d 19. bear Similar protrusions 21 fittinginto the grooves 20a-of rotor-11, while the protrusions ml of the;lattenprotrude into, similar grooves nta m diatetp iot sions..212. The-,-prot-rusions: and grooves 20, zed of rotor 11 on theoneshand-,.anda.pror trusiqns, and grooves 21, 21aof, wall 3 on theother. hand, are so disposed that" there is no friction between them,the rran ement, pmv dina; howeve for: a labyrinth; type sealing effectbetween the rotor 11, and surface 5 of wall 3.

The interior of rotor 11 comprises cooling spaces 22 whichare accessibleto theflow of, a coolant there,- through, for instance, by way,of;passages 23"and 24 opening into'transverse' channels 25'-'andi26"ir'1.rotor shaft 10.

In the cylindrical cavity defined" by wall; surface 6 or wellsg'33 and34; each- 'extending-axially alongone side of j the cylindrical surfaceof 'rotor' 30-?and :opposite on rotorfiflthat they allow-for passagetherethrough' of' pistons 13 and- 14 of the'--eentral" "rotor 1 13Instead of possessing separate internal combustion chambers-'- irr the"interiorof the' rotor-3ll asdoes the corresponding; rotor in my copending"patent-application Serial No. 688,908 supra, the'-rot or--3tl isprovided, in

accordancewith the present inventionywitha diametrically extendingchannel or conduit 35 connecting the 1 two wells :33' and 3'4:Conduit-35' may preferably have a narrowercross section at 'the-centerof "rotor SW-than when it opens into wells 33-and--34. -Wel-ls 33*and-34" together" with conduit 35 constitute thecombustion charnber in rotor30, thusleaving sufiicient space available in the interior of rotor 30for cooling-chamber.

Coolant is circulated through-the latter via coolant-pascorrespondingprotrusions 39am achievethe: same'labyrinth type sealing effectwith-surface-9 of wall-'3":

The'other cavity substantially 'oppositedhat 'cavity which houses-thecombustion rotor, and ,define'd-bycyL I indrical surface 7 dinner wall3"ofthe'casing'lhouses' a rotary abutment or--sealing'- rotor" 40, whichis mountedon a gate rotor shaft 41 and; is provided on its" externalcylindrical surface with-ribs and'grooves-4-21engaging with ribs andgrooves 17 on surface 1210f rotor 11 to"atta ina labyrinth-type sealingeffectas mentioned abovebetween rotors 11 and 40 Gate'recesses, orwells, 43- and-44 are provided inthecylindricalsurface of gate rotor 40at diametrically opposite'sidesofthe rotor. Pistons-13*and' 14of-centra1 rotor -11 passsuccessivelydhrough thesewells -43'-and-'44:during therotation of both rotors--11 and-AM The interior .ofrotor-40 comprises a coolingspace 45 through which coolant circulatesvia conduits- 46*and 47 "The end faces 48, 48a of rotor 40' are provided1 with annular protrusions and-groove means 49Whi0h engage-barre:

sponding means 49a -insurface-9 of inner casing: wall-'3" take conduit50 and an exhaust conduit 51 leading from the internal space housing thecentral rotor to the outside of external wall 2 of engine casing 1.

Furthermore, a transfer or bypass conduit 52 is provided in wall 3,which conduit leads from the opening 55 in the wall surface 5 of thespace housing thecentral rotor 11 behind a wall portion 59 to thesurface 6 of wall 3 defining the cavity which houses combustion rotor 30and opens into that cavity with a broad mouth 56. This bypass conduit 52is located on the side where the cylindrical surfaces of rotors 11 and30 separate, clockwise rotation of rotor 11 being assumed.

In the embodiment of the rotory engine illustrated in Figures 1 and 2the shaft 41 of sealing rotor 40 is parallel to shafts 10 and 31, butthegeometrical plane defined I by shafts 10 and 31 forms an angle on withgeomet-- rical plane defined by shafts 10 and 41. This arrangement hascertainadvantages to be described further below.

At the top end in a bore 54 which opens into the internal wall surface 6of the cavity housing the combustion rotor at some distance from theopening of conduit .52 thereinto. It is preferably slightly displacedfrom the geometrical plane the flywheel 67 connected in the usual way tothe starting motor 68.

The external piping for fuel and/or air intake and exhaust of wastegases, as well as for the admittance and Withdrawal of coolant, are wellknown in the art and omitted for the sake of clarity. a

Figure 3 shows an embodiment of an internal combustion rotor for rotaryengines in accordance with my invention, in which reference numeral 70designates-the combustion rotor shaft. The rotor body which is rigidlymounted on this shaft 70 comprises a head or end surface 71 bearingannular protrusions 72 and grooves 72a for effecting a labyrinth-typesealing with the adjacent wall of the engine casing, and a cylindricalmantle Wall 73 which bears over that portion of its external surfacewhich cooperates with the central rotor of the rotary engine, aplurality of ribs 74 and grooves 74a to achieve a labyrinth-type sealingeffect between the two rotors along their line of contact.

In the wall 73, there are provided at opposite sides of that wall, indiametrical position to each other, piston wells 75 and 76 which are ofrectangular longitudinal cross section, i. e. that cross section whichis taken in a plane parallel to the central rotor axis, and is ofsubstantially rectangular cross section in a plane radial to the rotoraxis.

A channel 77 of trumpet-shaped cross section connects wells 75 and 76freely communicating with each other. This channel 77 is preferably ofapproximately elliptic cross section taken in planes perpendicular tothe central longitudinal axis of the channel. Channel 77 is enclosed byinternal tubular wall 78 which is so devised that the narrowest crosssection of the channel 77 is at the point where the channel traversesthe rotor axis, while the largest cross sections are located wherechannel 77 opens into wells 75 and 76.

The remaining internal space of the rotor forms a cooling chamber 79through which a coolant is circulated via conduit 79a in shaft 70, andvia an axial outlet opening 79b.

of casing 1, a spark plug 53 is located 1 Another embodiment of thecombustion rotor for rotary engines in accordance with the invention isillustrated in Figure 4. The body 80 of theinternal combustion rotor inFigure 4 is of approximately ellipsoid shape except in the planespassing through the'rotor axis and in which the piston wells 82 and 83are located with their central cross section, and comprises otherwisethe same structure as the rotor illustrated in Figure 3.

However, wells 82 and 83 are of a concave shape rather than of therectangular box shape in Figure 3.

correspondingly the central rotor 84 cooperates with combustion rotor 80and is of a shape which is concavely complementary to the approximatelyellipsoid shape of the latter. Of course, it is al'sopossible toprovide, a central rotorhaving an approximately ellipsoid body,-and aconcavely complementary shape of the combustion rotor.

frusto ellipsoidal shape so as to pass as snugly as possible through thewells '82 and 83. I

Figure 5a illustrates the cross sectional contours of rotor 80 and oneof thewells 82, 83 taken in planes P P P P and P as indicated bydash-dotted lines in Figure 4, while Figure 5b illustrates rotor 84 andthe *contour lines of the cross sections of one of pistons 85 taken inthe same aforesaidplanes.

This preferred embodiment of the wells and pistons of the rotary enginein accordance with the invention comprising convex pistons and concavewells has the advantage that, as the wells represent the combustionchambers in the combustion rotor in accordance with this invention, thefront of the combustion flame is better propagated therein, in front ofthe pistons, than it is in wells and by pistons of known design.

The transverse profile of the pistons as it is shown in FigureSb'preferably comprises a flattened ridge 86 which contributes to animproved sealing effect. The latter may be further increased byproviding ribs and grooves 87 extending longitudinally along the ridge86.

In a further embodiment of the combustion rotor in accordance with theinvention as illustrated in Figure 6, the rotor body 90 comprises fourpiston wells 91, 92, 93 and 94 through which pass the pistons 95 of acentral rotor 96. vPiston wells 91 and 93 freely communicate with eachother by way of a conduit 97 disposed diametrically in rotor 90, wherebythese wells 91, 93 and conduit 97 form a first combustion space; wells92 and 94, on the other hand, are freely communicatingly connected by aconduit 98 disposed at right angle to conduit 97 and bypassing thelatter on a different plane with more than two pistons as has been setforth in my co-pending applications Ser. Nos. 574,833 and 688,908 supra.

Instead of being diametrically connected by conduits as illustrated inFigure 6, pairs of wells may be disposed next adjacent each other andconnected by conduits passing through the interior of the rotor body insuch a manner that the combustion spaces formed by each pair of Wellsand its connecting channel are disposed substantially parallel to eachother in the rotor body. In this system, two spark plugs must beprovided in the vicinity of the horizontal plane through the rotor axis,which plane extends perpendicularly to the plane common to the centralaxes of the combustion rotor and the central rotor. A plurality ofbypass channels open into the cavity housing the combustion rotor in thevicinity of the aforesaid plane at opposite sides of the last-mentionedThe central rotor 84 bears pistons 85, only oneof which is shown inFigure 4. The pistons 85 are of 1:. rotor and communicate-bothrfreelywith the central. space of the engine housing the, central rotor. inthe. region of thepower zone.

The combustion rotors in accordance with.- the. invention. and describedhereinbefore. may also be used in rotary engines other than that shownin Figures. 1 and 2. For instance; the different kinds of. rotaryengines disclosed in my co-pendingpatentapplications; Ser, Nos. 574,833and 688,908 supra caneasily be fitted out with these combustion rotors.use, Figure 7 illustrates a rotary engine comprising a calsing200 andtwo combustion rotors .201 and 202 therein, oi the type illustrated inFigure 1, cooperating with a central rotor 2.03 which. bears on itsperiphery five pistons 204, 205, 206, 2.0 7 and 208-. Theengine furthercomprises. two gate rotors 209, 21.0 arranged about the central rotor.203 alternatingly with-combustion rotors 201 and 202, and. intakeconduits.211a and exhaust conduits 212. The combustion. rotor 201. isprovided. with two wells 213 and 214 and a diametrically. disposedconnecting, channel215', while rotor 202ris provided similarly withwells'216 and 217 and a.v connecting channel 218. Eachof the rotorsfurther cooperates with a spark plug 219, 220, and a bypass conduit 221,222 respectively, which spark plugs and bypass conduits are provided inthe engine casing 200.

In order to guarantee a more complete scavenging of the combustion spaceconstituted. by, for. instance, the wells 213 and- 214 and connectingchannel. 215, the portiomof. the space housing the centrallrotor 203between the contactline of the latter with rotor. 20.1and the trai1- ingedge of the-departingpiston 207 is. preferably brought into connection.with the exhaust conduit, for instance, 212, somewhat before accessthereto isopened by piston 207 passing. the mouth 21241 of that conduihThis is achieved. by. recesses 223:in thewall enclosingthe internalchamber of the. casing. 200 housing the central'rotor 203. A.;similarrecess'may, of course, beprovided in the wall 3 of the rotary engineillustrated in Figure l, as-is shown in the. partial View of'the.exhaust. region thereof, shown in Figure 1a.

Operation The operation of a rotary engine comprising an internalcombustion rotor or rotors inaccordance with my invention shall beexplainedin detail, at the hand ofthe. embodiment of my inventionillustrated in Figures 1 and 2, five successive stages in the operationof this enginebeing schematically shown in Figures 8a to 8e.

It will be understood that the basic operation of the embodiment of arotary engine shown in these figures applies equally to the. functioningof the rotary engine illustrated in Figure 7 and to allsimilar rotary.engines provided with internal combustion rotors in accordance with myinvention.

In Figures 8a to 8b like reference numerals indicate like parts as inFigures 1 and 2';

The central rotor 11 is set in motion with the aid of auxiliary startingmotor 68 (Figure 2), for instance, a small ele'ctromotor, so that itrotatesclockwise as indicated by arrows in Figures 8a to 8e. The pistons13' and 140i central rotor 11, and the wall-of the latter whereit-contactsthe walls of. rotors 30and 40, subdivide's thecylindrical'central chamber enclosed by wall surface into..4 zones ofvarying volume:

(1.) An intake or aspiration zone A between the contact line of rotorslland.40 and the. trailing slope 13b or l ibof either piston 13.'or.14,

(2).A compression. zone C intermediate the leading slope (13aor14a)of-.either piston 13 or 14 and' the contact line between rotorsll and30,

(3) An expansion or power zone B intermediate the contact linebetween'rotors 11 and. 30 and the. trailing.

slope;(13b or 14b) ofthe .otherpiston, and.

(4); Amexhaust; zone Einterrnediate the; leading slope As only oneexample of such" (1311 or 1.4a);v of, the other: piston and the contactline, between rotorsl ls and 40.

Due to itsrotation in clockwise direction, piston 13 suctiensa: mixtureotzair and fuel inthe case of a controlled ignition carburator ty-p e ofengine, or of air alone in the case of a; fuelinjectiontypeof engine,via. intake conduit into the cylindrical-space enclosed by wall surface:5, the fluid following. the trailing slope. 13b of.

thispistonav v Ati'thesame time, the leading-slope 13a. of piston. 13.compresses the fluid. which; was, taken in by a previous cycle of rotor.11 in;the.compression' space A. positiondll-ustrated: in-Eigpre 8a,;well 33. of. combustion rotor-30in just; entering, into, communicationwith com? bustion space C, and thealready compressedfiuid from.

that space fills thewell-and penetrates. through channel 35 into.well34, scavenging ther residual burnt gasesfrom.

burnt waste gasesfrom-the wells-33. and 34- and the channel 35- by thescavenging step (Figure 8a) andthatthat communication is then cut off soas to avoid unnecessary losses-of fresh fluidescaping into the power,and exhaust zones;-

Shortly thereafter; upon further rotation. of, rotor 30 incounter-clockwiseandrotor:11in clockwise direction, .thecommunicationbetween well 34 and bypass conduit 52 is thus interrupted (Figure 8bandfurtheradvance of piston 13 leads to further compression of. the.coinbustion-fiuid inthe space: ZoneC+channel3i5+we1l 34. Upon furtherrotation, piston 13- penetrates into well 33 and the compression reachesits. maximum (Figure 80..)I when piston 13 is entirely in well 33.Concurrently with the interruption of. communication between well 34'and bypassconduitSZ, i. e. somewhat prior tothe fulllpenetration-of:piston 13 into well 33, piston 14 has begun to givezfree-passage tothe-waste. gases from zone P'and con,- duit 52. into. exhaust zone. B.This. is due to a suitable location of the exhaust passagev Slirel'ativeto the contact line between-rotors Hand 30.

Sparking of sparkplug 53.takes place preferably slightly before piston13. reaches dead center position in well 33. Aspiston 13 'passes this.dead center-point inv well 33', piston 14 has already movedpast thatpoint through Well 44.

The expanding hot. gaseous combustion products push the trailing edge13b of piston 13. and thus transmit power tothe central rotor shaft 10(Figure 8d). At the same time piston 14 has leftv well 44 and approachesintake opening: 50, while the leading edge 13a of piston 13 beginsto'push the waste gases of the previous cycle out through exhaustconduit, 51' (Figure 8d).

The trailing edge 13!) of piston 13 is further moved clockwise underpressure from the expanding burnt gases in the space constituted bypower zone P t-well 33+channel 35+well. 34. As the trailing ed'ge'33b ofwell 33 reaches wall portion59"intermediate bypass conduit 52' and thecentral chamber and cavity enclosedby wall surfaces 5 and 6', theleading edge 33a of well 33' opens communicationof the latter withbypass conduit 52 thus maintaining the above defined'expansion space.During the expansion of. the burnt gases behind the trailfing slope 13bof piston 13', the leading slope 14a of piston 14 cuts off the intakeconduit 50 from the zone forward of that piston and compresses the fluidtherein, whilesuctioning new fluid into the space behindthe pistonfollowing its trailing edge 14!) (Figure 8a).

Upon further rotation, piston 14' reaches the position In the l occupiedby piston 13 in'Figure 8a, and the cycle of operation described above isrepeated.

As will be seen from the different figures, and preferably in Figure I,particularly in engines of the carburetor type the angular displacementof intake '50 relative to the line of contact between rotors l and 11and taken at the axis of the central rotor, is so chosen, thatcommunication between the explosive mixture (fuel containing explosivemixture) entering through the intake port 50, on the one hand, and theexhaust Zone on the other hand, by way of wells 43 and 44, of sealingrotor 40 is effectively prevented.

Furthermore, in order to avoid that theintake stroke is unnecessarilyshortened as compared with the exhaust stroke, the position of the axisof sealing rotor 40 is located in a plane passing through the axis ofthe central rotor, which plane forms a slight angle a, with the planecommon to the axes of central rotor 11 and combustion rotor 30, thedisplacement being toward the exhaust part. Thereby the intake and theexhaust strokes are made substantially of equal length as described inmy copending application Ser. No.688,908 supra.

Advantages The feature of my invention that the wells of the internalcombustion rotor serve at the same time as the combustion chamber of therotary engine, offers the following advantages:

(a) Cooling of the rotor is more space in the interior of the rotor isavailable for passing coolant therethrough than if separate combustionchambers would be provided apart from the wells.

(b) The cooling effect can be uniformly extended to all walls, bothexternal and internal of the combustion rotor, since all of these wallscan be provided of substantially uniform thickness. Y

c) Substantially all of the hot waste gases left in the wells and theconnecting channel in the interior of the combustion rotor can beeffectively scavenged by fresh fluid pushing these waste gases outthrough the bypass conduit 52; at the same time, the fresh fluid beingat a much lower temperature than the hot waste gases, acts as anadditional coolant for the internal walls of the combustion rotor.

(d) The introduction of an undesirably large amount of waste gases froma preceding into the next following work cycle is avoided and theexpulsion of carbon and the like residues is facilitated.

(e) The combustion which takes place in one of two wells of thecombustion rotor connected by an internal channel, and in the channelitself heats the walls of the latter as well as of the aforesaid welland thereby provides a certain preheating of the next following chargeof fresh gas prior to the combustion of the latter.

(f) The turbulence of the gas caused by their passage into thewell-connecting channel in the combustion rotor provides for a betterhomogenization of the fuel containing gas mixture and accelerates theinflammation of the mixture.

The particular shape and dimensions of the channel connecting the wellsin the combustion rotor in accordance with my invention are so devisedas to facilitate the passage of fluid therethrough during the expansionstage of the work cycle. Thus, the channel is of a somewhat smallercross section than the cross section of the pistons at their ridge ortop surface.

Further advantages reside in the placement of the spark plug or plugs intheexternal wall of the casing, whereby more space is available in theinterior of the combustion and in the adjacent part of the casing forproviding cooling spaces for the passing of coolant therethrough, whilein the previous arrangement this space had to be sacrificed for thelocation of the spark plugs. These additional cooling spaces aredesignated by 4a and 4b in Figure 2.

greatly facilitated sincestate also permits the use of smaller rolling,contact bearings such as ball bearings 101 and the sealing means 102about the shaft 31 ofrotor 30 externally of the bearing 101 are of muchsmaller internal diameter and consequently a smaller friction-causingcontact surface with the rotor shaft 31, than is the case for instance,in the arrangement of previous combustion rotors.

Also, it'is easier to attach the electrical spark control system to thespark plug or plugs, and they are more easily cooled and replaceable.

While, in earlier constructions, such as those of my pending patentapplications Ser. Nos. 574,833 and 688,- 908 supra, a separate exhaustchannel for the combustion rotor had to be provided, this separatechannel is made unnecessary in the system ofv my present invention and asingle exhaust conduit for the central rotor exhaust space and thecorresponding combustion rotor is sufficient. I I

While the invention has beenexplained in detail above at the hand ofexamples of a rotary engine of the carburator'type, i. e. which isprovided with a controlled ignition system, the same invention can alsoeasily be applied in rotary engines of the fuel injection and compression ignition or diesel type.

In this case, the spark plugs in the above described embodiments of myinvention are replaced by fuel injectors which are disposed inclinedrelative to the plane through the combustion rotor axis so as to bringabout ignition of the compressed air fuel mixture at maximumcompression, i. e. at dead center position of the piston in the well ofthe combustion rotor.

In the same manner, this invention may also be-applied to a fuelinjector type'engine having a controlled ignition system. In this case afuel injector and a spark plug are arranged with each pair of wells of acombustion rotor of the type described in accordance with the invention,that fuel is first injected .intothe combustion chamber consisting ofwells and connecting channel in the combustion rotor, and that theresulting compressed air fuel mixture is then ignited, stillsubstantially in the range of dead center position, by means of thespark plug.

It will be understood that this invention is susceptible to modificationin order to adapt it to different usages and conditions and,accordingly, it is desired to comprehend such modifications within thisinvention as may fall within the scope of the appended claims.

What I claim is:

1. In a rotary engine of the type described and having internalcombustion rotor means with wells therein for the passage of the pistonsof the central rotor of said engine, the improvement of channel meansconnecting every two wells in said combustion rotor means with eachother, and said two wells and the channel means connecting the sameconstituting together one integral combustion space in said combustionrotor.

2. In a rotary engine of the type described and having an internalcombustion rotor with wells therein for the passage of the pistons ofthe central rotor of said engine, the improvement of channel meanswithin said combustion rotor and connecting the wells of said combustionrotor in pairs with each other, and constituting together with each pairof wells a combustion chamber in said combustion rotor.

3. In a rotary engine of the type described, the improvement comprisingat least one internal combustion rotor having at least one pair of wellsin the external' surface of said rotor, and a channel within theinterior of said rotor and connecting the two wells of said pair freelycommunicatingly'with each other, so as to provide a continuouscombustion chamber within said rotor.

4. The improvement described in claim 1, wherein said channel means passthrough the central axis of the combustion rotor. i

5,. The improvement described in claim 3, wherein said channel is sodisposed as 'toconnect two wells cated diametrically opposite each otherin the external rotor surface: l

p 6. In a rotary engine of the type described, the improvementcomprising at least one internal combustion rotor having. a plurality,of. pairs of wells in the external surface of said rotor, the two wellsof each pair being diametrically disposed relative to. the rotor. axis,and a plurality of channels within the. interior of said rotor andconnecting the two wells of each pair freely communicatingly with eachother, soas to provide a plurality of continuous combustion chamberswithin said rotor.

. 7; In. a rotary engine of the type described and. having,

and means causing the ignition of a combustible mixture in saidcombustion chamber and disposed in the external wall of the enginecasing.

8. The improvement as described in claim 7, wherein saidignition-causing means comprise at least one electrical spark plug. I

9. The improvement as described in claim 7 wherein said ignition-causingmeansv comprise fuel injector means.

10. The. improvement as described in claim 7 wherein saidignition-causing means comprise fuel. injector means together with atleast oneelectrical spark plug.

11. A rotaryengine of the internal combustion type comprising, incombination, a casing, wall means in said casing enclosing an annularcentral chamber, and a number of cavities laterally disposed of andopening into said central chamber, a central rotor rotatably mounted insaid central chamber, a plurality of pistons projecting outwardly fromsaid central rotor and fittinginto said central chamber for frictionlessrotation therein, a combustion rotor rotatably mounted in one of saidlateral cavities, a gate rotor rotatably mounted in another of saidlateral cavities, the axes of rotation of said central rotor, saidcombustion rotor and said gate rotor being parallel to each other, said.combustion rotor. comprising two wells for the passage of said pistonstherethrough, which wells are disposed diametrically opposite each otherin the combustion rotor and open toward the outside thereof, and aninternal channel connecting said two wellsv with each other, said wellsand channel in said combustion rotor constituting a combustion chambertherein, exhaust conduit means in said casing opening into said centralchamber, said central chamber being subdividedv into an intake zone, acompression zone, a power zone and. an exhaust zone during thesynchronized rotation of said rotors in conjunction with rotation ofsaid pistons through said central chamber, a bypass conduit leading fromthe cavity housing said combustion rotor to said central chamber throughthe wall of said casing so as to provide communication between a well ofsaid combustion rotor and a space between the latter rotor and a pistonof said central rotor when said piston has travelled a predetermineddistance after leaving said well, means for introducing and igniting acombustible fluid mixture in said combustion chamber of said combustionrotor and comprising intake conduit means in said casing wall, gearmeans for causing rotation in unison of said central rotor, combustionrotor, and gate rotor, and a starting motor adapted for startingrotation of said central rotor.

12. A rotary engine of the internal combustion type comprising, incombination, a casing, wall means in said casing enclosing an annularcentral-chamber, and a-number of. cavities laterally disposed of andopening into said central chamber, a central rotor rotatably mounted insaid central chamber, a plurality of pistons projecting.

outwardly from said central rotor and fitting into said central chamberfor frictionless rotation therein, a combustionv rotor rotatably mountedin one of said lateral cavities, a gate rotor rotatably mounted inanother of said lateral cavities, the axes of rotation of said centralrotor, said combustion rotor and said gate rotor being parallel to eachother, said combustion rotor comprising two wells for the passage ofsaid pistons therethrough, which wells are disposed diametricallyopposite each other in the combustion rotor and open toward the outsidethereof, and an internal channel connecting said two wells with eachother, said wells and channel in said combustion rotor constituting acombustion chamber therein,exhaust conduit means in said casing openinginto said central chamber, said central chamber being subdivided into anintake zone, a compression zone, a power zone and an exhaust zone duringthe synchronized rotation of said rotors in conjunction with rotation ofsaid pistons through said central chamber, a bypass conduit leading fromthe cavity housing said combustion rotor to said central chamber throughthe wall of said casing so as to provide communication between a well ofsaid combustion rotor and a space between the latter rotor and a pistonof said central rotor when'said piston has travelled a predetermineddistance after leaving said well, means for introducing and igniting acombustible fluid mixture in said combustion chamber of saidcombustionrotor and comprising intake conduit means in said casing wall, and aspark plug located in the portion of the wall of said casing surroundingthe peripheral inner wall enclosing said cavity. of said combustionrotor, gear means for causing rotation in unison of-said central rotor,combustion rotor, and gate rotor, and a starting motor adapted forstarting rotation of said central rotor.

13. A rotary engine of the internal combustion type comprising, incombination, a casing, wall means in said casing enclosing an annularcentral chamber, and a number of. cavities laterally disposed of andopening into said central chamber, a central rotor rotatably mounted insaid central chamber, a plurality of pistons projecting outwardly fromsaid central rotor and fitting into said central chamber forfrictionless rotation therein, a combustion rotor rotatably mounted inone of said lateral cavities, a gate rotor rotatably mounted in anotherof said lateral cavities, the axes of rotation of said central rotor,sai-d combustion rotor and said gate rotor being parallel to each other,said combustion rotor comprising two wells for the passage of saidpistons therethrough, which wells are disposed diametrically oppositeeach other in the combustion rotor and open toward the outside thereof,and an internal channel connecting said two wells with each other, saidwells and channel in said combustion rotor constituting a combustion.chamber therein, exhaust conduit means in said casing opening into saidcentral chamber, said central chamber being.

subdivided into an intake zone, a compression zone, a power zone and anexhaust zone during the synchronized rotation of saidrotors inconjunction with rotation of said pistons through said central chamber,a bypass conduit leading from the cavity housing said combustion rotorto said central chamber through the wall of said casing so as toprovidecommunication between a well of said combustion rotor and a spacebetween the latter. rotor and apiston of said'central rotor when saidpistonhasttravelled a predetermined distance after leaving said well,means for introducing and igniting a combustible fluid. mixture in saidcombustion chamber of said combustion rotor'and comprising intakeconduit means in said. casing wall, and a spark plug located in theportion of the wall of. said casing surroundingthe peripheral inner wallenclosingisaid: cavity of said C0111,- bustion rotor, in the zone ofsaid inner wall intermediate the limits defined, on the one handby theopening of,

said bypass channel. into said combustion rotor cavity the wells of saidcombustion rotor in that position of the latter in which the other wellconnected to the former well by said internal channel is filledsubstantially completely by a piston of said central rotor; gear meansfor causing rotation in unison of said central rotor, combustion rotor,and gate rotor, and a starting motor adapted for starting rotation ofsaid central rotor.

14. A rotary engine of the internal combustion type comprising, incombination, a casing, wall means in said casing enclosing an annularcentral chamber, and a number of cavities laterally disposed of andopening into said central chamber, a central rotor rotatably mounted insaid central chamber, a plurality of pistons projecting outwardly fromsaid central rotor and fitting into said central chamber forfrictionless rotation therein, a combustion rotor rotatably mounted inone of said lateral cavities, a gate rotor rotatably mounted in anotherof said lateral cavities, the axes of rotation of said central rotor,said combustion rotor and said gate rotor being parallel to each other,said combustion rotor comprising two wells for the passage of saidpistons therethrough,

which Wells are disposed diametrically opposite each other in thecombustion rotor and open toward the outside thereof, and an internalchannel connecting said two wells with each other, said wells andchannel in said combustion rotor constituting a combustion chambertherein, exhaust conduit means in said casing opening into said centralchamber, said central chamber being subdivided into an intake zone, acompression zone, a power zone and an exhaust zone during thesynchronized rotation of said rotors in conjunction with rotation ofsaid pistons through said central chamber, a bypass conduit leading fromthe cavity housing said combustion rotor to said central chamber throughthe Wall of said casing so as to provide communication between a well ofsaid combustion rotor and a space between the latter rotor and a pistonof said central rotor when said piston has travelled a predetermineddistance after leaving said well, means for introducing and igniting acombustible fluid mixture in said combustion chamber of said combustionrotor and comprising intake conduit means in said casing wall, for theadmission of a comburent, and fuel injection means, gear means forcausing rotation in unison of said central rotor, combustion rotor, andgate rotor, and a starting motor adapted for starting rotation of saidcentral rotor.

15. A rotary engine of the internal combustion type comprising, incombination, a casing, wall means in said casing enclosing an annularcentral chamber, and a number of cavities laterally disposed of andopening into said central chamber, a central rotor rotatably mounted 14in said central chamber, a plurality of pistons projecting outwardlyfrom said central rotor and fitting into said central chamber forfrictionless rotation therein, at least one combustion roto'r rotatablymounted in one of said lateral cavities, at least one gate rotorrotatably mounted in another of said lateral cavities, the axes ofrotation of said central rotor, said combustion rotor and said gaterotor being parallel to each other, said combustion rotor comprising atleast one pair of wells for the passage of said pistons therethrough,which wells are disposed diametrically opposite each other in thecombustion rotor and open toward the outside thereof, and an internalchannel connecting the two wells of said pair with each other, saidwells and channel in said combustion rotor constituting a combustionchamber therein, intake and exhaust conduits in said casing opening intosaid central chamber, at least one bypass conduit, said bypass conduitleading through the casing wall from the cavity housing said combustionrotor to said central chamber, and opening thereintoso as to providecommunication between a well of said combustion rotor and a spacebetween the latter rotor and a piston of said central rotor when saidpiston has travelled a predetermined distance after leaving said well,means for igniting a combustible fluid mixture in said combustionchamber of said combustion rotor, gear means for causing rotation inunison of said central rotor, combustion rotor, and gate rotor, and astarting motor adapted for starting rotation of said central rotor.

16. A rotary engine as described in claim 11, wherein said bypasschannel opens into said cavity housing said combustion rotor at suchposition relative to the intersection of said cavity with said centralchamber and to said exhaust part in the wall of the latter, that freecommunication is established between said compression zone of saidcentral chamber and said exhaust part via the two wells of saidcombustion rotor, the internal channel connecting said pair of wells,said bypass channel and the exhaust Zone of said central chamber for ashort time so as to permit scavenging of the several aforesaid spaces bymeans of fresh gaseous fluid compressed in front of the leading slope ofa piston of said central rotor approaching the intersection of saidcentral chamber with said combustion rotor cavity, While avoidingsubstantial losses of fresh gaseous fluid by cutting off theabove-mentioned free communication prior to a substantial amount of saidfresh fluid penetrating through said bypass channel into said powerzone.

No references cited.

